Update dependencies to the latest versions
- Go version bumped from 1.18 to 1.23
- aws-sdk-go-v2 updated to v1.32, with dependent modules further increase (e.g. eks v1.50)
- aws/smithy-go (code generator) updated to v1.22
- slack-go updated to v0.14
- spf13/cobra updated to 1.8.1, as well as other maintenance code (e.g. testify, multierr, zap, for testing)